“Surf, Sand, and Stone”—Did You Miss It?

Everyone attending Keith Meldahl’s April presentation at BVAS was treated to the nerve rattling and often side-splitting topic of California geology, including tectonic plates and earthquakes. Sometimes over millions of years and sometimes in a violent minute, California has morphed into the golden state of today.

Here’s the “CliffsNotes” version of Keith’s talk.

*We all have our faults! In fact, there are hundreds crisscrossing the 200-mile wide boundary zone between the North American (think Yuma) and Pacific Plates (think Oceanside). The king of them all is the San Andreas, stretching from the Salton Sea north toward Eureka.

*We’re all moving north! At least, all of us on the San Diego County coast who are catching a ride on the Pacific Plate. At about two inches a year, we should be off San Francisco in 14 – 15 million years. Be patient.

*Claim dual-citizenship! The journey north doesn’t begin here. In fact, some of the round pebbles and cobbles on our beaches and in our cliffs began in Sonora, Mexico. They tumbled down the ancient rivers to the sea, and have been slowly carried north ever since. Se habla español?

*Shake, rattle, and roll! It’s been over 100 years since the 1906 San Francisco quake, but more than 300 years since the big one on the southern San Andreas. Such events open like a zipper; in this case the force likely travels north through Palm Desert and goes left through the faults and unstable soils of the LA basin. We lose Grandma’s china; LA loses LA.

*In the meantime, just relax. Go to the beach perhaps, which will continue to be covered in sand as long as our rivers flow freely, our cliffs erode naturally, and wetlands like the Buena Vista Lagoon are open to the sea. In this, we can make a difference. Choosing the best restoration plan for the Buena Vista Lagoon will directly impact the amount of sand naturally deposited on our North County beaches. More sand equals better coastline protection, as well as enhanced recreational opportunities.

To learn more, you can order Surf, Sand, and Stone: How Waves, Earthquakes, and Other Forces Shape the Southern California Coast, from www.smile.amazon.com